[SWODY1] SWODY1

[SWODY1 at goshenarc.org]

ACUS01 KWNS 201257
SWODY1
SPC AC 201252

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0752 AM CDT MON SEP 20 2004

VALID 201300Z - 211200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 35 S
GLD 35 NW GLD 40 E SNY 60 E CDR 40 SE PHP 45 S PIR 30 SSW 9V9 35 E
ANW 10 SE BBW 15 WSW HLC 60 SW HLC 35 S GLD.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 SE ELP 50 SW ROW
20 S TAD 10 N LIC 35 WSW AKO 35 ENE DEN 15 W DEN 15 SSE ASE 25 NE
DRO 20 NNW FMN 30 WSW CEZ 30 ENE U17 15 ENE BCE 20 N SGU 65 N DRA 35
SSW TPH 65 S NFL 20 ESE RNO 25 ESE 4LW 15 SSW PDT 35 NNE 63S
...CONT... 50 NNE FCA 25 WSW HLN 30 S HLN 30 NNE BZN 65 W MLS 45 NW
REJ 30 NE Y22 50 E P24 55 NE MOT ...CONT... 80 NW CMX 30 NW RST 55
WSW DSM 30 SW FNB 15 SW SLN 40 SE GAG 45 SSW LTS 45 W ABI 50 W SJT
70 WSW SJT 45 NW DRT.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM LRD 40 NW ALI NIR 15
S VCT 20 ESE PSX.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 25 W CTY 40 S AYS 30
NE SSI.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF WCNTRL
NEB...FAR SRN SD...FAR NW KS AND FAR NE CO...

...HIGH PLAINS/CNTRL PLAINS AND WRN PART OF SRN PLAINS...
A COLD FRONT CURRENTLY LOCATED ACROSS WRN SD WILL ORGANIZE AND DROP
SWD INTO NWRN NEB BY LATE THIS AFTERNOON. THIS WILL PROVIDE A FOCUS
FOR CONVECTIVE DEVELOPMENT AS INSTABILITY INCREASES ACROSS THE
REGION. A DEEPLY MIXED LAYER EVIDENT ON WV IMAGERY OVER WRN CO WILL
SPREAD EWD INTO WRN NEB AND WRN KS. THIS WILL ALLOW FOR STRONG SFC
HEATING AND MODERATE INSTABILITY SHOULD DEVELOP THIS AFTERNOON.
MODEL FORECASTS APPEAR TO BE UNDERESTIMATING THE AMOUNT OF MLCAPE
WHICH SHOULD REACH THE 1000 TO 1500 J/KG RANGE BY 21Z WHICH WILL BE
SUPPORTIVE OF STRONG UPDRAFTS. INITIATION SHOULD FIRST OCCUR ALONG
OR JUST AHEAD OF THE FRONTAL BOUNDARY NEAR RAPID CITY WITH CELLS
LIKELY DEVELOPING SWD INTO WRN NEB THIS AFTERNOON. THE STORMS SHOULD
GRADUALLY EXPAND IN COVERAGE AND MOVE ESEWD INTO THE INSTABILITY
AXIS LATE THIS AFTERNOON AND EARLY THIS EVENING. OTHER STORMS WILL
LIKELY DEVELOP ACROSS WRN KS AND POSSIBLY AS FAR SOUTH AS THE TX
PANHANDLE. HOWEVER...THE STORMS WILL BE ISOLATED DUE TO A CAPPING
INVERSION. THE SRN EXTENT OF CONVECTION WILL DEPEND ON HOW MUCH THE
CAP WEAKENS LATE THIS AFTERNOON.

STORMS THAT INITIATE ALONG THE FRONT AND DEVELOP SWD ALONG THE SFC
TROUGH WILL HAVE ACCESS TO STRONG VERTICAL SHEAR DUE TO AN
APPROACHING LARGE UPPER-TROUGH OVER THE WRN US. A PLUME OF STEEP
MID-LEVEL LAPSE RATES IN EXCESS OF 8.0 C/KM...WILL SPREAD OUT INTO
WRN NEB AND FAR WRN KS AS THE UPPER-TROUGH SHIFTS EWD...FAVORING AN
ISOLATED LARGE HAIL THREAT WITH SUPERCELLS MOVING ESEWD ACROSS
WCNTRL NEB AND WRN KS. ALSO...FORECAST SOUNDINGS SUGGEST LOW-LEVEL
LAPSE RATES WILL EXCEED 10.0 C/KM ACROSS WRN KS AND WRN NEB. THIS
COMBINED WITH INVERTED-V SOUNDING PROFILES SHOULD RESULT IN A WIND
DAMAGE THREAT WITH THE FASTER...MORE ORGANIZED STORMS.

...FL...
SFC ANALYSIS CURRENTLY SHOWS A MOIST AXIS JUST OFF THE ERN COAST OF
FL WITH MID 70S F DEWPOINTS IN PLACE. SCATTERED STORMS ARE ONGOING
IN THE MOIST AXIS AND STORM DEVELOPMENT SHOULD CONTINUE THIS MORNING
AND AFTERNOON AS INSTABILITY INCREASES. MLCAPE VALUES SHOULD REACH
THE 2000 TO 3000 J/KG RANGE AND THIS WILL BE SUFFICIENT FOR STRONG
UPDRAFTS AS CELLS MOVE ONSHORE FROM THE EAST NORTHEAST. FORECAST
SOUNDINGS SHOW RELATIVELY WEAK SHEAR PROFILES. THIS COMBINED WITH
HIGH BOUNDARY LAYER MOISTURE CONTENT WILL BE FAVORABLE FOR SFC-BASED
MULTICELLS WITH A POTENTIAL FOR STRONG OUTFLOW. THE MODERATE
INSTABILITY...HIGH SFC DEWPOINTS AND DRY AIR ABOVE 700 MB MAY BE
ENOUGH FOR A MARGINAL WIND DAMAGE THREAT THIS AFTERNOON. A BRIEF
LANDSPOUT TORNADO WILL ALSO BE POSSIBLE AS CELLS QUICKLY DEVELOP
ALONG INTERACTING OUTFLOW BOUNDARIES THIS AFTERNOON.

..BROYLES/JEWELL.. 09/20/2004

...NOTICE...
FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.